War of the Portuguese Succession

The War of the Portuguese Succession (1580-1583) was a war fought between Spain and its allied nobles from Portugal and those Portuguese forces loyal to Antonio, Prior of Crato, backed by France, England, and the United Provinces. The war resulted in Philip II of Spain's accession to the throne of Portugal, creating the Iberian Union.

In 1580, following the disappearance of King Sebastian of Portugal at the Battle of Alcacer Quibir, Antonio, Prior of Crato proclaimed himself as King of Portugal and the Algarves. He governed for just 33 days before King Philip II's Spanish armies invaded Portugal, claiming the throne for the House of Habsburg. Fernando Alvarez de Toledo's Spanish army defeated the Portuguese at Alcantara on 25 August 1580, and the Duke of Alba conquered the capital of Lisbon two days later. In 1581, the Prior of Crato fled to France, and Antonio and the French adventurer Piero Strozzi sailed to the Azores, Antonio's last stronghold. In 1582, the Franco-Portuguese forces were defeated in two naval battles off the Azores, and England's attempted invasion of the Azores also failed. From 1583 to 1640, the Spanish Empire and the Portuguese Empire were united as the "Iberian Union".